Artillery shells typically utilize a fuse installed at the leading end of the shell. The fuse may be a mechanical or electronic device designed to control the detonation of the explosive charge (ex—payload) of the shell. A number of currently available artillery shell fuses include electronics and telemetry systems for promoting improved accuracy and detonation control. Electronic circuits disposed in the fuse remain in radio-frequency contact with a ground station after launch of the shell for coordinating the trajectory of the shell and making course corrections as necessary. Further, the artillery fuse may operate in conjunction with a satellite-based positioning system, such as the NAVSTAR global positioning systems (GPS), maintained and operated by the United States government, for accurately determining the coordinates of the shell as it travels along its trajectory and reaches the point of impact, and for correcting the trajectories of subsequently fired munitions. GPS may also be used as a positional reference to deploy retractable airfoil flaps of an artillery shell, from a previous free fall state, to more accurately control the downward descent of the artillery shell towards the target.
An artillery shell fuse having telemetry and positioning system electronics requires an antenna suitable for the application and environment to which an artillery shell is subject. A number of currently available antennas have radiation patterns which are omni-directional in orthogonal directions about the shell trajectory and thus, may be capable of being jammed from terrestrial positions. Other currently available antennas may be subject to performance degradation effects including carrier-phase roll up, phase carrier wrap, and roll-ripple due to antenna asymmetry.
Thus, it would be desirable to have an antenna system for artillery shells which addresses the problems associated with current solutions.